I've heard of it, sounds to me like just a gimmick toy that you would buy, use once or twice and then forget about it in your drawer. If you wear watches, you want an all-in-one smart watch or you want a nice looking piece of jewelry.
I personally don't think it'll do well and I think there is a reason these guys are going down the route of crowdfunding... Angel investors and venture capitalists do not want to fund it.
RE: Wearable tech?